[Dislocations and fractures of the ossicles--high resolution computerized tomography of the petrous bone]

As in traumatology of the head the HR-CT of the injured petrous bone is now the imaging method of choice. With axial and coronary slices one can show not only the different parts of the ear but also the course of the facial nerve and particularly the ossicles in the tympanon. The fractures are nice to show, also the soft tissue lesions like brainprolaps in the tympanon or hematotympanon because of the better density resolution in comparison to the conventional tomography with rather higher radiation dose especially for the eye lenses. Important are the slice thickness of 1.5 mm with special examination technique, that also small fractures of the pyramid particularly the labyrinthous organ and of the ossicles mostly associated with dislocations are detectable. Regarding that with the clinical possibilities there are particular consequences for the otosurgeon. The ossicular dislocations of other than traumatic cause are rare.